Priority is claimed on Japanese Patent Application No. 2006-236603, filed Aug. 31, 2006, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a motor control device.
2. Description of the Related Art
Heretofore a motor equipped with a first permanent magnet piece and a second permanent magnet piece for which the phase positions are mutually changeable by means of, for example, servo pressure, so that the magnetic field flux can be changed, is known (for example refer to Japanese Unexamined Patent Application, First Publication No. S55-153300).
Furthermore, heretofore for example in motors such as for hybrid vehicles, those provided with an adjustment mechanism in which a plurality of rotors, which are provided with magnetic poles with polarities that are serially different in the rotation direction, are arranged on the same rotation axis such that they are adjacent, and the induced voltage constant of a permanent magnet with respect to the stator is adjusted by changing the spacing of these rotors by means of an actuator, is known (for example refer to Japanese Unexamined Patent Application, First Publication No. 2001-69609).
Incidentally, in a motor according to the abovementioned conventional technology, in a case where current control is performed based on a torque command which is set for example corresponding to accelerator opening or the like related to the accelerator operation of the driver, so that a difference between a current command value and a current detection value with respect to the energizing current of the motor becomes zero, when the relative phase of the plurality of rotors is changed, there is the possibility that it becomes difficult to appropriately perform current control. That is to say, in the feedback control of the current, the induced voltage constant is set to a predetermined value. However, since this is an assumption, then when the induced voltage constant changes due to the change in the relative phases of the plurality of rotors, there is the possibility that it becomes difficult to make the current detection value converge on the current command value.
There present invention was made in view of the aforementioned circumstances and has an object of providing a motor control device that is capable of performing appropriate current control with respect to the energizing current of the motor, even in the case where the induced voltage constant of the motor changes.